White light scattering from non-Gaussian rough surfaces

Abstract

A method is proposed for calculating the spectral correlation function of light intensity scattered from non-Gaussian rough surfaces. The correlation function of a spectral speckle of scattered light is analyzed taking into account the surface correlation properties, roughness height, shape of its distribution, and the observation angle. A difference in the form of the stationary correlation function from the predicted one, which increases with the deviation of the roughness height distribution from the normal one, is found for non-Gaussian diffusers. The effect of the scattering problem dimension and the type of statistical model describing the roughness on the characteristics of scattered light is analyzed. It is shown that for non-Gaussian rough surfaces the assumption about normal roughness height distribution may lead to errors in measuring the roughness parameters by the methods of optical diagnostics based on analysis of scattered light parameters.